• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.268-274
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• 1984

The purpose of this study was to investigate the physico-chemical effects of a potato starch and a purified potato starch under the condition of the microwave heating. They were exposed to the microwave energy in a 950 W, 2,450 MHz oven for 30 through 120 seconds. As the microwave heating time was increased, the contents of moisture and the crude fat of the samples were remarkably decreased irrespective of the starch composition, but on the other hand the contents of crude ash was slightly decreased and the crude protein was almost unchanged. The rings of crystallinity come to gradually changed in the X-ray diffraction pattern, and then the only 1 ring, of which interplanner spacing is wide, is changed strikingly. As the microwave heating time is increased, the starch granules which observed by a scanning electron microscope were broken partially with a special form, and the granules of purified potato starch were broken faster than those of potato starch. With the same condition that the microwave heating time was increased, while the gelatinization temperature comes to fall, the swelling power and the solubility were increased. Besides these, while the gelatinization temperature of the purified potato starch was lower than that of the potato starch, both the swelling power and the solubility of the purified potato starch is higher than those of the potato starch.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1274-1284
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• 2009

Single crystals of fully dehydrated and fully $Ca^{2+}$-exchanged zeolites A (|$Ca_6$|[$Si_{12}Al_{12}O_{48}$]-LTA) and X (|$Ca_{46}$| [$Si_{100}Al_{92}O_{384}$]-FAU) were brought into contact with Te in fine pyrex capillaries at 623 K and 673 K, respectively, for 5 days. Crystal structures of Te-sorbed $Ca^{2+}$-exchanged zeolites A and X have been determined by single-crystal X-ray diffraction techniques at 294 K in the cubic space group Pm$\overline{3}$ m (a = 12.288(2) $\AA$) and Fd $\overline{3}$ (a = 25.012(1) $\AA$), respectively. The crystal structures of pale red-brown |$Ca_6Te_3$|[$Si_{12}Al_{12}O_{48}$]-LTA and black coloured |$Ca_{46}Te_8$| [$Si_{100}Al_{92}O_{384}$]-FAU have been refined to the final error indices of $R_1/wR_2\;=\;0.1096/0.2768\;and\;R_1/wR_2$ = 0.1054/ 0.2979 with 204 and 282 reflections for which $F_o\;>\;4{\sigma}(F_o)$, respectively. In the structure of |Ca6Te3|[$Si_{12}Al_{12}O_{48}$]- LTA, 6 $Ca^{2+}$ ions per unit cell were found at one crystallographic positions, on 3-fold axes equipoints of opposite 6-rings. In |$Ca_{46}Te_8$|[$Si_{100}Al_{92}O_{384}$]-FAU, 46 $Ca^{2+}$ ions per unit cell were found at four crystallographically distinct positions: 3 $Ca^{2+}$ ions at Ca(1) fill the 16 equivalent positions of site I, 21 $Ca^{2+}$ ions at Ca(2) fill the 32 equivalent positions of site I’, 10 and 12 $Ca^{2+}$ ions at Ca(3) and Ca(4), respectively, fill the 32 equivalent positions of site II. The Te clusters are stabilized by interaction with cations and framework oxygen. In sodalite units, Te-Te distances of 2.86(10) and 2.69(4) $\AA$ in zeolites A and X, respectively exhibited strong covalent properties due to their interaction with $Ca^{2+}$ ions. On the other hand, in large cavity and supercage, those of 2.99(3) and 2.76(11) $\AA$ in zeolites A and X, respectively, showed ionic properties because alternative ionic interaction was formed through framework oxygen at one end and $Ca^{2+}$ cations at the other end.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3696-3701
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• 2011

The single-crystal structure of partially dehydrated partially $Mg^{2+}$-exchanged zeolite Y, ${\mid}Mg{30.5}Na_{14}(H_2O)_{2.5}{\mid}$ [$Si_{117}Al_{75}O_{384}$]-FAU per unit cell, ${\alpha}$ = 25.5060(1) ${\AA}$, dehydrated at 723 K and $1{\times}10^{-4}$ Pa, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd$\bar{3}$ m at 100(1) K. The structure was refined using all intensities to the final error indices (using only the 561 reflections with $F_{\circ}$ > $4{\sigma}(F_{\circ})$) $R_1$ = 0.0377 (Based on F) and $R_2$ = 0.1032 (Based on $F^2$). About 30.5 $Mg^{2+}$ ions per unit cell are found at four different crystallographic sites. The 14 $Mg^{2+}$ ions occupy at site I at the center of double 6-ring (Mg-O = 2.231(3) ${\AA}$, O-Mg-O = $89.15(11)^{\circ}$ and $90.85(11)^{\circ}$). Four $Mg^{2+}$ ions are found at site I' in the sodalite cavity; the $Mg^{2+}$ ions are recessed 1.22 ${\AA}$ into the sodalite cavity from their 3-oxygen plane (Mg-O = 2.20(3) ${\AA}$ and O-Mg-O = $92.3(14)^{\circ}$). Site II' positions (opposite single 6-rings in the sodalite cage) are occupied by 2.5 $Mg^{2+}$ ions, each coordinated to an $H_2O$ molecule (Mg-O = 2.187(20) ${\AA}$ and O-Mg-O = $114.2(16)^{\circ}$). The 10 $Mg^{2+}$ ions are nearly three-quarters filled at site II in the supercage, being recessed 0.12 ${\AA}$ into the supercage (Mg-O = 2.123(4) A and O-Mg-O = $119.70(19)^{\circ}$). About 14 $Na^+$ ions per unit cell are found at one crystallographic site; the $Na^+$ ions are located at site II in the supercage (Na-O = 2.234(7) ${\AA}$ and O-Mg-O = $110.5(4)^{\circ}$).

• Journal of Ginseng Research
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• v.26 no.1
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• pp.1-5
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• 2002

It has been well known that Korea red ginseng has an antihypertensive effect. The antihypertensive effect may be due to its ability to change the peripheral resistance. Change of vascular tone in the resistance-sized artery contribute to the peripheral resistance, thereby regulate the blood pressure. Therefore, we investigated to clarify the vasorelaxing mechanism induced by crude saponin of Korea red ginseng in the resistance-sized mesenteric artery of rats. The resistance-sized mesenteric artery was isolated and cut into a ring. The ring segment was immersed in HEPES-buffered solution and its isometric tension was measured using myograph force-displacement transducer. Crude saponin of ginseng relaxed the mesenmetric arterial rings precontracted with norepinephrine (3$\mu$M) in dose-dependent manner (0.01 mg/㎖ -1 mg/㎖. The relaxation by crude saponin was smaller in endothelium-intact preparation than that in endothelium-denuded preparation. The contraction induced by A23187 or phorbol 12,13-dibutyrate was not affected by crude saponin of ginseng. The vasorelaxing effect of crude saponin of ginseng was significantly attenuated by the increase of the extracellular K$\^$+/ concentration. Crude saponin-induced vasorelaxation was not affected by tetraethylammonium (1 mM), glybenclamide (10$\mu$M), and 4-aminopyridine (0.1 mM) in these preparations. Ba$\^$2+/(10$\mu$M ∼100$\mu$M) markedly reduced the crude saponin-induced vasorelakation dose-dependently. From the above results, we suggest that crude saponin of ginseng may stimulate K$\^$+/ efflux and hyperpolarize the membrane, thereby cause the vasorelaxation in the resistance-sized mesenteric artery of rats.

• Korean Journal of Plant Taxonomy
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• v.33 no.3
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• pp.255-270
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• 2003

Pollen morphology of four genera (Daphne L. - 4 spp., Edgeworthia Meisn. - 1 sp., Wikstroemia Endl. - 2 spp., and Stellera L. 1 sp.), except 1 taxon (Diarthron Turcz. - 1 sp.) in Korean Thymelaeaceae were examined with light (LM) and scanning electron microscopy (SEM). The size of grains ($11.3-60.0{\mu}m$) are varied from small (in Stellera) through medium (in Daphne and Wikstroemia) to large (in Edgeworthia). All studied taxa have monad, spheroidal, pantoporate (10-20) grains. The exine is reticulate, especially a typical "croton pattern" which is comprising rings of more or less trihedral subunits. Each triangular subunit is topped by a single microspinule, and the surface pattern is psilale. In Daphne, three types of subunit arrangement can be recognized; - (1) Type I : subunits are arranged circles and attached to each other or sometimes fused in part, (2) Type II: each subunit is trihedral and isolated distinctly, and (3) Type III: each subunit is isolated, but somewhat vague. Systematic implication of the present pollen data for the Korean Thymelaeaceae is also briefly discussed.

• YAKHAK HOEJI
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• v.41 no.6
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• pp.802-816
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• 1997

In order to investigate the pharmacological properties of New Woohwangehungsimwon Pill (NWCH). Effects of Woohwangehungsimwon Pill (WCH) and NWCH were compared using various experimental models. In isolated rat aorta, NWCH and WCH showed the relaxation of blood vessels in maximum contractile response to phenylephrine ($10^{-6}$M) without regard to endothelium containing or denuded rings of the rat aorta. Furthermore, the presence of the inhibitors of NO synthase and guanylate cyclase did not affect significantly the relaxative effects of NWCH and WCH. NWCH and WCH inhibited the vascular contractions induced by acethylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats(SHRs), NWCH and WCH decreased significantly heart rate. These, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, these had no effects on parameters of action potential at low doses, whereas inhibited the cardiac, contractility at high doses. Furthermore, these had a significant inhibitory effects on heart acceleration in normotensive rats and SHRs. These results suggested that NWCH and WCH have weak cardiovascular effects, and that there is no significant differences between two preparations.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.717-724
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• 2011

The objectives of this study were to analyze environment in the forest and growth characteristics for investigating the characteristics of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast. As a result of analyzing inhibitory factors of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast, it is considered that the salt level included in a sea wind is supposed to be the primary factor of the slow growth for Robinia pseudoacacia since brown leaves, wilting and early leaf fall have appeared in the 0m spot from the artificial dune which has the high salt level. However, the soil properties and light environment hardly have a effect on the growth of Robinia pseudoacacia because there is no difference among planting places. Also, the growth ring of the horizontal root in 2year individuals 0.1~0.2m away from the dune have been formed for 1 year only as a consequence of analyzing growth rings of Robinia pseudoacacia growing on the coast. It can be infered that the nourishment of the horizontal root from individuals growing on the coast have been provided for the first 1 year only. It is estimated that, in case of the nearby areas on the coast, it is not enough to provided nourishment to the horizontal root due to obstructing the growth of new individuals by a sea wind, so the growth of the horizontal root would be hampered. Therefore, it is considered that impedient Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast is caused by making no growth of new horizontal roots and newborn individuals.

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.36-43
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• 1996

The crystal structure Tris(ethylenediamine)nickel(II)Dichromate has been determined by X-ray crystallography. Crystal data: a=8.268(2), b=13.865(2), c=14.921(2)Å, γ=102.04(2)°, V=1672.9(5)Å3, Z=4, Monocline, P21/b (space group No.=14), Dcalc=1.806 gcm-3, μ=24.05 cm-0.1. The intensity data were collected with Mo-Kα radiation(λ=0.7107Å) on an automatic four-circle diffractometer with a graphite monochromator. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were R=0.045, Rw=0.051, Rall=0.059 and S=2.171for 2248 observed reflections. The two carbon atoms of a ring of Ni(en)-ion were split into crossed four atoms. In consideration of α- and β-angles of two rings of a disordered ethylenediamine of Nien3-ion and the hydrogen bonds between Ni(en)3-cation and Cr2O7-anion, the configuration of Ni(en)3-ion is assumed to be disordered with Λδδδ and Λδδλ.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.10
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• pp.1040-1049
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• 2014

In this paper, a quad-band antenna for DCS1800, PCS1900, WCDMA, WLAN and Mobile WiMAX application is proposed. The proposed antenna is a printed monopole structure, and consists of two rectangular ring-shaped radiating patches on the front side and two different size of L-shaped slots on the back side(ground plane). Two rectangular ring radiation patches are respectively resonant at 2 GHz and 3.5 GHz bands, and additional resonance is occurred at 5.3 GHz by the coupling effect between two ring patches. In addition, the optimized matching characteristic is obtained by controlling the gaps. Also, by adding two L-slots on the ground plane, additional resonant frequency band of 5.6 GHz is occurred. Finally the measured bandwidths of the proposed antenna below -10 dB return loss are 1,200 MHz(1.6~2.8 GHz), 800 MHz(3.2~4.0 GHz), 300 MHz(5.14~5.44 GHz), and 690 MHz(5.56~6.25 GHz). The radiation patterns have the omni-directional characteristic, and the measured antenna average gains at resonant bands are 0.86~4.07 dBi.

• Journal of radiological science and technology
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• v.29 no.1
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• pp.13-19
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• 2006

The PET scanner can detect the photon pair arriving from the source in phantom. The number of light photons released by the crystal(scintillator-BGO or LSO). In recent scintillation crystals in block structures were incorporated into full ring systems, and their resulted marked improvement in spatial resolution and increase in a sensitivity to annihilations. The uniformity of the crystal sensitivity is very important to makes correct information of abnormal states in organs. These factors influenced by the dection efficiency of the scintillators. We have study about the uniformity of crystals to the annihilation, And study about the standard deviation to average counts. The relative standard deviation in central detector groups more uniformed than circumferenced detector groups. It is caused detected quanta of gamma ray by the geometrical factors of PET detector. PET cameras are available with different geometric arrangement and several parallel rings oriented in the axial direction. The center groups from 7th to 40th groups are comparatively uniform and sensitive. But at the circumferenced detectors decreased the sensitivity and uniformity.